Patch id3 v0.78 to be compiled under cygwin

charconv.cpp
5a6
> #include <cstring>
getid3v2.cpp
2a3
> #include <cstring>
setfname.cpp
1a2
> #include <cstring>
makefile
7c7
< CFLAGS     = -g -O2
---
> CFLAGS     = -g -O2
193c193
<   $(CXX) $(OBJECTS:=.o) $(LDFLAGS) -o $@
---
>   $(CXX) $(CXXFLAGS) $(OBJECTS:=.o) $(LDFLAGS) -o $@